this is what i thought, but then i remembered the time microsoft passed on buying google.
i'm wondering not so much about whether or not apple's purchase impacts the xbox, whether or not microsoft not snapping up the company is a mistake. of course i only think that because apple decided to buy it. if lenovo had bought the company i probably wouldn't have even posted anythign about it.
I doubt it affects the xbox or MS in any drastic way. In this case it's more of Apple playing catchup this time, since they realize that voice recognition controls and gesture based controls are the next area to get into- an area that MS already has a healthy head start in Kinect 360 and XB1 Kinect, integrating the technology smoothly into a living entertainment product, the years of in-house research that has gone into it, and a pretty healthy developer community that has been making use of Kinect technology for real world applications (medical research, helping the disabled, 3D scanning, etc.). Whatever IP MS needed from that company to develop their tech, they more than likely already owned it before Apples acquisition.
Apple acquiring PrimeSense helps them to reduce their development time by bringing experience in house, but the still have to turn it into a usable package that people will want to buy. Apple TV, while a very nice product, has never moved out of the niche-category. If Apple is looking to design an all-in-one TV with Kinect like gesture/voice control, they may face the same problems of the new product being stuck to a niche as well, especially if priced high compared to buying a XB1+a new or existing 1080p TV, which would offer greater functionality anyways in the form of doing the exact same thing
and being able to play AAA games. There are now also rumors that MS is only 6 months away from releasing an "XB1 lite" that would be a low cost, media only device (basically apple TV), but share the core functionality of XB1's OS and media services. It was supposed to come out earlier but was delayed due to the XB1 launch.
XBOX One without gaming coming - Paul Thurrott - Microsoft Console - Neowin Forums
TLDR: still not really a big deal.